1. Field of the Invention
The present invention relates to a system for distributing moving image data through a network, and more particularly to a moving image distribution system which is capable of making phase adjustment of video data and audio data.
2. Description of the Related Art
In recent years, the distribution of moving image data through a network has been growing. Display apparatus such as projectors can be connected to a moving image distribution server through a network for receiving moving image data distributed from the moving image distribution server. A display apparatus reproduces video and audio data from the moving image distribution server based on a system clock signal, as disclosed in JP-A No. 11-275519.
Display apparatus process various video signals such as composite signals, RGB signals, etc. to display images represented by those video signals. Video signal processing schemes include an I/P conversion process for converting an interlaced video signal into a progressive video signal and a process for converting the resolution of a video signal to a value that matches the display apparatus.
However, the video signal processing processes are problematic in that they produce a delay in the display of video data and the delay shifts the image out of phase with the corresponding audio data by several fields, causing the viewer to feel odd about the asynchronous display. In order to solve the problem, it is necessary to delay the audio data with a delay circuit for bringing the video data and the audio data into phase with each other.
According to the above moving image distribution system, however, the cost of the display apparatus increases due to the addition of the delay circuit for delaying the sound in order to bring the video data and the audio data into phase with each other.